Greenspan, who spoke on NBC's "Meet the Press," said he believed "something equivalent to what Bowles and Simpson put out is going to be approved by Congress. But the only question
is whether it is before or after a crisis in the bond market."

He said the risk is that the deficit, which hit $1.3 trillion this year, could spook the bond market. That would result in long-term interest rates moving up rapidly and could lead to a double-dip recession.